1. Field of the Invention
This invention relates to a method and apparatus for reversing or inverting a supplemental restraint cushion on air bag and, more particularly, this invention relates to inverting an air bag and subsequently actuating the air bag to flatten panels forming the air bag against each other.
2. Related Prior Art
Air bags are increasingly used as an additional or supplemental restraint system in automobiles, and there is a corresponding increasing need for manufacturing methods and apparatus which facilitate the construction of the air bags and thereby also reduce the time and cost of constructing the air bags. Conventional air bags are typically formed of a main panel and a face panel which are sewn together along their peripheral edges whereby a cavity is defined between the two panels. After the panels are joined together, the air bag must be reversed or inverted through an aperture in the main panel in order to locate the seam extending around the periphery of the air bag within an interior portion of the bag. In addition, the air bag must also be flattened after it is inverted in order to prepare the air bag for a folding operation wherein the air bag is folded into a compact configuration for storage in the steering wheel or dashboard of a vehicle.
In one known method of reversing an airbag, the air bag is placed on a first plate having an aperture therethrough with the aperture in the main panel facing the aperture of the plate. A plunger is actuated to extend into contact with the face panel to thereby force it through the apertures in the main panel and the plate. Pressurized air is then supplied to the interior of the reversed air bag to cause it to expand outwardly, and another plate is then moved toward the first plate to flatten the air bag therebetween. This method of reversing and flattening an air bag is relatively labor intensive in that the aperture of the air bag must be manually aligned onto the aperture of the first plate, and it is also necessary to first expand the air bag with air prior to performing the flattening operation.
Accordingly, there is a need for a method and apparatus for easily and quickly inverting and flattening successive air bags.